Goodwill and Intangible Assets - Changes in Goodwill for Each Reportable Segment (Detail) $ in Millions	3 Months Ended
Dec. 31, 2021 USD ($)
Goodwill [Roll Forward]
Beginning balance	$ 1,830
Acquisitions (a)	130
Other adjustments	(15)
Ending balance	1,945
Recorded Music
Goodwill [Roll Forward]
Beginning balance	1,366
Acquisitions (a)	130
Other adjustments	(15)
Ending balance	1,481
Music Publishing
Goodwill [Roll Forward]
Beginning balance	464
Acquisitions (a)	0
Other adjustments	0
Ending balance	$ 464

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
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-Name Accounting Standards Codification
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Reference 3: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

+ References

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- Definition

Amount of increase (decrease), classified as other, of an asset representing the future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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